Indicator attachment for fuses



March 23, 1937. L. A. KAUFFMAN 7 INDICATOR ATTACHMENT FOR FUSES Filed June 5, 3.936

Patented Mar. 23, 1937 UNITED STATES PATENT OFFICE Leroy A. Kauflman, Washington,

D. 0., assignor to Indicating Fuse Manufacturing Corporation, Washington, D. 0., a corporation of Delaware Application June 5, 1936, Serial No. 83,758

4 Claims.

The present invention relates to indicators for circuit breakers and more particularly to an attachment for fuses of the cartridge type which when the fuse becomes blown or ruptured, a visible signal will be displayed for continuously indicating the inoperative condition of the fuse, having amongst its principal objects the provision of a new article of manufacture which when applied to a fuse of the cartridge type will not only prol0 vide a visible indicator therefor but will provide a handheld which will greatly facilitate the insertion and removal of the fuse from its block or clips.

A further object of the present invention is to provide a device of the aforesaid character having a body portion or casing made of insulating material for housing the contacts and other electrical connections in order that when it is applied to a fuse, it will not only provide a handhold therefor but will greatly reduce the chances of the operator receiving shocks when inserting or Withdrawing the fuse from its base or clips, thereby producing a safety handhold for fuses.

A still further object of the present invention is to provide a detachable connection between fuses and indicators therefor which will permit the indicator to be easily and readily applied to the fuse or removed therefrom or be adjusted at various angles with respect thereto whereby a signal may be displayed when the fuse becomes blown or ruptured at an angle suitable for ready detection.

Other objects of the invention will be in part obvious and in part pointed out hereinafter.

In order that the invention and its mode of operation may be readily understood by persons skilled in the art, I have in the accompanying illustrative drawing and in the detailed following description based thereupon, set out an embodi- 0 ment of the same.

In the drawing:

Figure 1 is a plan view of the indicator embodying the present invention.

Figure 2 is a longitudinal section through the indicator when applied to a fuse of the cartridge typ Figure 3 is a vertical transverse section through the indicator, taken on the line 3-3 of Figure 2 in the direction of the arrow points.

Figure 4 is another detailed transverse section taken on the line 4-4 of Figure 2 in the di rectlon of the arrow points, and

Figure 5 is an end elevation of the indicator when applied to a fuse mounted in its fuse clips, 55 showing the position of the indicator at right angles to that illustrated in Figure 2 and on a. reduced scale.

Referring now more particularly to the accom panying drawing wherein like and corresponding parts are designated by similar reference characters throughout the several views, the numeral l designates the fibre shell or casing of a fuse of the cartridge type and 2, the end terminals thereof, which latter are retained in frictional contact with the clips 3 of the cutout base. The usual fuse link (not shown) is arranged within the casing l and is connected to the terminals 2, whereby should a short circuit occur in the line in which is included the clips 3, the fuse link will become blown or ruptured for breaking the circult.

The indicator attachment for such conventional types of fuses and electrical circuits thereof is preferably dctachably connected to the fuse so that when the fuse link thereof becomes blown, H

a continuous visible signal will be displayed. This indicator comprises a body portion 4 of a substantially cylindrical configuration and made of a suitable insulating material such as porcelain, Bakelite and the like. This casing has a central recess 5 formed therein and communicating with the opposite ends of this recess 5 are longitudinally extending channelways or grooves 6. A sight opening 7 is also formed within the casing 4 and communicates with the recess or compartment 5.

This recess or compartment is substantially ot a rectangular configuration having an opened end and in this opened end is snugly fitted a partition or support 8. This support 8 is preferably stamped from a piece of fibre and has also a rectangular configuration. Contact clips 9 each having one end it secured to the support 8 and their opposite or free ends fitting within the longitudinally extending grooves 6 of the casing 4. These contact clips are preferably made of brass in order that they may have electrical contact with the terminals 2 of the fuse.

A lamp indicator ll of the neon type is supported upon this partition 8 and having its lead wires connected to the inner ends ill of the contact clips 9. Arranged between one of the leads of this lamp and a clip 9 is a leak resistance l2 which is supported and carried by the partition 8.

In order to retain the indicator upon a fuse of the cartridge type, I preferably and do employ a locking ring Hi. This locking ring is of a substantially 8 configuration and is made of fibre or other suitable insulating material. A smaller opening of this locking ring l3 fits over the body cator.

portion or casing 4 whereas the larger opening Id of this ring is placed over a shell or casing l of the fuse in the manner as better illustrated in Figure 2 of the drawing. Lugs or shoulder projections i5 are also formed with this ring it and upon which is seated the partition 8 in order to retain the latter in the lower opened end of the recess or lamp compartment 5 of the casing in the manner as better illustrated in Figure 3 of the drawing.

From the construction as herein set forth, it is obvious that the ring E3 will, when applied. to the casing l, retain the partition 3 therein as well as the lamp and the contact clips 2 carried thereby. As the smaller end of this ring is slipped over the casing i, a loose or pivotal connection is established so that one end of the fuse may be inserted through the opening is of. this ring and by giving the casing a slight turn, the clips 3 will be brought into contact with the terminals 2 so as to retain the casing in a position longitudinally of the fuse. The outer free ends of the clips 9 are provided with beaded projections it which extend over the opposite ends of the fuse, thereby establishing a locking connection between the indicator and the fuse which will prevent any longitudinal movement of the indicator upon the fuse when once so applied.

At times, it is desired to have direct contact between the indicator and the terminals of the fuse whereupon the indicator will be mounted directly upon the fuse and when a signal dis played through the sight opening it may be viewed by looking directly down upon the indi- At other times, it is impractical to so mount the indicators directly upon the fuse, that is, when a fuse box has not the required depth to accommodate this position of the indicator in order that the cover of the fuse box may be properly closed without contacting the s and therefore, due to the locking ring connection between the indicator and fuse, the indicator may be rotated about the fuse casing l, whereupon the indicator may be moved at different angles with respect to the fuse. In Figure 5 of the drawing, I have illustrated the indicator as being positioned to the side of the fuse or at a position at right angles to that shown in ine 2 of the drawing. To cause the indicator to assume this latter position when the flared ends of the clips are relatively long, it is first necessary to remove the fuse I from the clips, then place the outer extremities of the clips at one side of the fuse plug between the contact clips 9 and the ferrules 2 of the fuse and by again forcing the fuse l within the clips 3, the indicator will be retained in position as is shown in Figure 5 of the drawing. The contact clips 9 are moved out of engagement with the terminals 2 and caused to contact directly with the clips 3 of the cutout base. When moving the indicator to this latter position, the clips 9 must be moved over the outer flared ends of the clips 3, but in some cases, it is possible to arrange the clips 9 between the clips 3 and the ferrules 3 of. the fuse.

From the construction of the indicator and its attaching ring it, it is quite obvious that one may clasp the casing 4 and use the latter as a han hold for removing the fuse from its contact clips 3 or inserting the same therein without the fear of contacting the clips 3 or the terminals 2 which would likely cause a shock to the operator. Also, the operator may readily adjust the indicator with respect to the fuse in order that it may assume a position directly above the fuse as that indicated in Figure 2 of the drawing or may be moved to the opposite sides of the fuse as is illustrated in Figure 5 of the drawing.

The casing 4 may be made of, any suitable transparent or translucent material so as to eliminate the sight opening 1 and permit the light from the glow lamp ii to penetrate through such translucent or transparent material. In the manufacture of my indicators, a support 8 may have the lamp attached thereto as well as the spring contacts 8 and when using a plastic transparent or translucent material, the casing may be molded about the support and the lamp thereon instead of first making a molded casing 4 with a lamp compartment therein for receiving the lamp and support.

Manifestly, the construction herein shown is capable of considerable modification and such modifications as come within the scope of my claims, I consider within the spirit of my invention.

I claim:---

1. An indicator and handhold attachment for cartridge type fuses comprising a support of insulating material, a pair of spring contact terminals carried by and secured to said support, a glow lamp mounted upon said support, a leak resistance, said lamp and leak resistance being connected in series with said terminals, a housing of insulating material extending over said support and lamp mounted thereupon, a ring of insulating material securing said casing to said fuse and shoulders formed within said ring for holding said support within said casing.

22. A detachable indicator for cartridge type fuses comprising a casing of substantially the same length as said fuse, said casing having a recess formed in one side thereof, a glow lamp indicator positioned within said recess, a partition for holding said lamp within said recess, a pair of spring contact terminals each extending to one outer end of said casing and having their opposite ends secured to said partition, a beadformed upon the free end of said terminals for gripping the outer ends of said fuse and limiting the longitudinal movement of said casing, a leak resistance, said lamp and leak resistance being. connected in series with said terminals, and a: means holding said casing against said fuse and holding said partition within the recess of said casing.

3. A detachable indicator for cartridge type fuses comprising a body portion composed of insulating material, said body portion having a central recess of substantially a rectangular configuration, a glow lamp indicator positioned within said central recess, a partition sized to fit within said central recess and supporting said lamp therein, electrical conducting means connected to said partition and the lead wires of said lamp, a leak resistance interposed between and electrically connecting one of said lead wires to one of said conducting means, said body having a sight opening formed therein exposing a portion of said lamp to view, and a means holding said partition in said recess and for attaching said body portion to a cartridge type fuse.

l. A detachable indicator and handhold for cartridge type fuses comprising a body portion composed of insulating material, a lamp compartment formed in the central portion of said body and having an opened end, a neon lamp indicator positioned within said lamp compartment, a partition of insulating material sized to fit within and close the opened end of said lamp compartment, a pair of electrical conducting strips each having one end connected to and extending through said partition, a pair of lead wires for 5 said lamp electrically connected to said strips, a leak resistance interposed between one lead wire of said lamp and one of said strips, said body having a sight opening formed therein exposing a. portion of said lamp to view, a ring composed of insulating material for holding said body portion against said fuse, and shoulder projections formed within said ring for holding said partition in said recess.

LEROY A. KAUFFMAN. 

